It is well known to provide a sidepocket mandrel, as shown in U.S. Pat. No. 3,741,299, having threaded end connections about a bore at each end for connection in a well tubing in which the mandrel body has an open bore in longitudinal alignment with the end bores and a sidepocket offset from the open bore for receiving flow control devices. However, the tubing string and mandrel are enclosed in a well and consequently the lateral space available to provide the internal diameter of the open bore is limited. The open bore and the end bores must have a lateral drift dimension or an internal diameter substantially equal to the bore of the well tubing for avoiding a restriction to the passage of well tools through the mandrel. These various space limitations have created a need for a mandrel in which the longitudinal axis of the open bore is offset from the longitudinal axis of the end bores.
However, with an offset open bore, many well tools that are only slightly smaller than the internal diameter of the well tubing have a length such that the tool cannot pass between one of the end bores and the offset open bore.
The present invention is directed to an improved sidepocket mandrel having an offset open bore with respect to the end bores which will allow a well tool of a predetermined length and outside diameter to readily pass through the mandrel.